按月份统计当月记录数select pid,DATE_FORMAT(adddate,''%Y%c''),count(*) as abc from T_TONE_LOG group by pid,DATE_FORMAT(adddate,''%Y%c'')%Y 年 %c 月 连和查询（找出 t1 在t2 中没有的）select * from T_COMPANY_SINGER_SONG as t1 left join T_SONG_NEW as t2 on (t1.song_id = t2.id)wher